Tilting table for ergometer and for other biomedical devices

ABSTRACT

The apparatus is for testing the human body in a variety of positions, ranging from the vertical to the supine, while exercising on an ergometer; and can also be used for angular positioning of other biomedical devices. It includes a floor plate and a hinged plate upon which to fix the ergometer, a back rest and a head rest attached at right angles to said hinged plate and behind the seat of the ergometer, dual hydraulic cylinders for raising and lowering the hinged plate through 90* by means of a self contained hydraulic system, with valve means for control and positive stops on the apparatus to prevent over travel. Tests can be made with the subject positioned on the seat of the ergometer, through the various angles, with a substantially normal body attitude relative to said seat and ergometer.

Gause et al.

Aug. 7, 1973 TILTING TABLE FOR ERGOME'IER AND FOR OTHER BIOMEDICALDEVICES Inventors: Raymond L. Gause; Raymond A.

Spier, both of Huntsville, Ala.

The United States of America as represented by the National Aeronauticsand Space Administration Filed: May 8, 1972 Appl. No.: 251,609

Assignee:

US. Cl. 73/379 Int. Cl. 60" 5/02 Field of Search 73/379; 272/73, 57;

References Cited UNITED STATES PATENTS 10/1962 Jaeger 73/379 5/1972Williams 128/24 R Primary Examiner-Charles A. Ruehl Attorney-L. D.Wofford, Jr.. J. R. Manning. et al.

[57] ABSTRACT The apparatus is for testing the human body in a varietyof positions, ranging from the vertical to the supine, while exercisingon an ergometer; and can also be used for angular positioning of otherbiomedical devices. it includes a floorplate and a hinged plate uponwhich to fix the ergometer, a back rest and a head rest attached atright angles to said hingedplate and behind the seat of the ergometer,dual hydraulic cylinders for raising and lowering the hinged platethrough 90 by means of a self contained hydraulic system, with valvemeans for control and positive stops on the apparatus to prevent overtravel. Tests can be made with the subject positioned on the seat of theergometer, through the various angles, with a substantially normal bodyattitude relative to said seat and ergometer.

9 Claims, 5 Drawing Figures PAIENTEDAUE 1191s SHEET 2 OF 3 WOE TILTINGTABLE FOR ERGOMETER AND FOR OTHER BIOMEDICAL DEVICES ORIGIN OF THEINVENTION The invention described herein was made by employees of theUnited States Government and may be manufactured and used by or for theGovernment for governmental purposes without the payment of anyroyalties thereon or therefor.

BACKGROUND OF THE INVENTION 1. Field of the Invention The inventionrelates in general to devices for testing the human body, and it dealsmore particularly with apparatus designed for testing the human body ina variety of positions ranging from vertical to supine while exercisingon the ergometer. It may also be used for angular positioning of otherbiomedical devices. It is necessary in preparation for manned spaceflight to determine the effects upon the human body of work performed bythe body in the different attitudes which may be assumed during spaceflight or while working in space such as those environmental conditionswhich might be experienced in a space station. Various tests need to beperformed upon the subject,'such as rate of heart beat, oxygenconsumption, metabolism, blood circulation, and the like. For thesepurposes, it is necessary that the body of the subject be maintained insubstantially a normal attitude assumed relative to the work to beperformed. It is often also necessary that the testing devicesthemselves be maintained in a relative position of this kind during thetests being performed. No existing equipment of this type is known.Previous methods involved the clamping of the base of the ergometer to awall or against a table. The disadvantage of this method is that theoperator can exercise only in the normal position or in the supineposition with his back on the floor, but with the attitude of the bodyrelative to the testing equipment in obviously an abnormal position.

2. Discussion of Prior Art After competent search, no existing devicesof this type were found, there being two references which wereconsidered, but which do not appear to conflict with the presentinvention or anticipate either the apparatus or the objects and purposesfor which it was designed. The prior art discloses the following UnitedStates Patents:

T. S. Swarts S. Jaffe Swarts discloses a body exerciser including a backrest plate 42 and a seat plate 36 which are hinged together at 46, andare angularly adjustable mechanically. This device is purely designedfor the purpose of exercising the body. The Swarts patent states on page1, column 2, lines 37-45, that the area of the spine and titude relativeto the exercising apparatus, thereby placing abnormal conditions ofstrain and tension on the body organs.

The patent to .laffe discloses a body muscle building machine which haspedals and can be used while seated on the floor, or in a chair or lyingdown. Again, the subject, while resting on the fabric 20, attempting toassume various angles of body elevation relative to the exercisingpedals, will completely change his body attitude relative to theexercising device. Neither of these references contemplated in any waythe combination of mechanical parts arranged and fixed so that thesubject was indexed into a stable position without regard to beinghorizontal or vertical, or in between the two, and therefore the testdata with regard to heart rate, oxygen consumption, blood circulation,and the like, would be in terms different due to the variances in theangular strain placed upon the various organs of the body as it isshifted in its attitude relative to the exercising means.

Neither of these references show a device which would serve or could beadapted to serve the need of the applicants nor is there a suggestion ofany such device, such as the one indicated in the present invention,wherein the body attitude relative to the testing equipment is notchanged as the apparatus is positioned through the various angles withthe body of the subject indexed into the same relative position withregard to the testing apparatus, without additidnal strain induced bythe changing angular position of the body.

SUMMARY AND OBJECTS OF THE INVENTION The primary object of thisinvention is to provide apparatus for testing the human body whileexercising in a variety of positions, ranging from the vertical to thesupine.

A salient feature in connection therewith is the provision of anadjustable platform which will selectively position the test subject andtesting apparatus at various predetermined angles.

A further important object is to provide angularly adjustable apparatusfor testing the human body in such varied positions without theintroduction of external stress factors unrelated to the primary test ofthe factor imposed by angularity.

A feature of importance, therefore, is the provision in the presentinvention of a tilting table to accommodate the test subject and theexercise apparatus, or other biomedical device, positioned operablethrough a variety of angles; wherein the body attitude of the testsubject relative to the testing equipment is not changed as theapparatus is thus moved through the various angles, but indexed into thesame relative position without additional strain induced by a change ofposition.

In effect, we have provided apparatus, for testing certain bodyfunctions, such as heart rate, oxygen consumption, blood circulation andmetabolic changes, and the like, wherein a human subject may assume afixed body attitude relative to the test equipment. The subject may thenbe positioned, along with his test equipment, through various angles,from vertical to supine, without changing the body attitude relative tothe equipment, free of angular strains which would be encountered insuch attitude change; and true measurements may be madeof changes inbody functions due solely to the effect of the change of the total bodyangle.

It can readily be seen that this can be of prime importance in testingthe body in a weightless atmosphere, such as might be encountered inspace exploration; and such experiments as may be conducted in a spacelaboratory.

It then becomes a further object to provide means whereby the apparatusmay be controlled such that the subject may angle himself over therange, or the same may be accomplished by remote controls or by anautomatic programmed control system.

A feature of the invention resides in a two-way hydraulic valve systemto control angularity by minimal movements of the test subject to changehis position, as well as the provision of remote control or programmedmeans for such purpose. The apparatus can be used with the ergometer asherein shown, but it can be employed with other biomedical devices, suchas the LBNPD, etc.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of the TiltingTable showing the device in the vertical position.

FIG. 2 is a side view of the Tilting Table, showing the device in anangular position relative to the horizontal.

FIG. 3 is a side view of the Tilting Table, showing the device in thehorizontal position.

All of the foregoing show the test subject as seated (in dotted lines)and indexed in fixed position relative to the equipment.

FIG. 4 is a diagrammatic illustration of a remote control switch whichcan be substituted for the subject operated hand switch toggle.

FIG. 5 is a diagrammatic illustration of an automatic programmed controlwhich can be similarly substituted.

DETAILED DESCRIPTION OF THE INVENTION Referring more particularly to thedrawings, FIGS. 1, 2 and 3, it can be seen that we have shown anembodiment of the invention using the conventional ergometer as abiomedical device for the purpose of imposing upon the body of a testsubject a work load which will be reflected in certain functionalchanges in the body as it performs work through an angular range fromthe vertical to the supine.

The device as shown includes a floor plate 1 and a hinged plate 2. Theplate 2 is provided with a configuration at its rearward edge forming anupturned flange which will provide a positive stop in the horizontalposition as the plate 2 is pivoted about the hinge 3 which fastens it toplate 1 as illustrated.

A tubular frame 6 is welded or otherwise fastened to the plate 2 flushwith the plate end at the hinge 3. This tubular frame is in the shape ofan inverted U extending to approximately the top of the head of a seatedsubject, and is expanded in width at about the height of seat 5 which isattached to plate 2 and accommodates the backrest 7. Somewhat below thispoint it is offset backward to allow for the thickness of the backrest.

The padding of the backrest 7 at the top eight inches or so is broughtforward to form a headrest 8. The amount depends upon the softness ofthe padding, but it should form around the neck and head, and thebackrest also should be made of resilient material, such as foam coveredwith cloth, so that when the body rests against them there is adefinite, though small, give which aids in maintaining position, in asemi-contoured manner relative to the subject positioned on the seat 5.In like manner, a projection for the headrest 8 is placed behind thebackrest to contact the floor when the device is in the horizontalposition, as indicated in FIG. 3.

Dual hydraulic cylinders 9 are flexibly attached to the plate 2 by meansof pivotal support blocks 10.

The piston rods 11 working in the cylinders 9 are flexibly attached toan car 12 formed by a plate tying the two sides of the tubular frametogether at a point slightly below the seat 5. The cars 12 and rods 11are projecting slightly forward of the main body of the frame 6, asindicated in FIGS. 1, 2 and 3.

In the embodiment shown, one of the ears 12, for example near thesubject's right hand, supports a two-way hydraulic valve mechanism 13having a toggle switch or lever 14 adapted to be operated with minimummovement by the hand of the subject 23 (indicated by the dotted lines innormal position on the apparatus); thus allowing the test subject toeasily adjust his own angle, by means of the hydraulic system,throughout a range from vertical to supine.

It can readily be seen that the valve mechanism 13 and hand lever 14 caneasily be replaced by a remote control valve and lever mechanism 15, asillustrated in FIG. 4, or by a remote control automatic programmingdevice 16 as diagrammatically illustrated in FIG. 5. Thus the subjectcould be put through all of the angles and also through a cycle ofangles over a time period, as might be desired.

The self contained hydraulic system itself, which could consist of astandard motor, pump, secondary reservoir and release valve, isillustrated as shown and designated by the numeral 17.

In the illustration shown, the hinged plate 2 supports an ergometerstand 4, having an adjustable seat 5 and handlebars 19.

To the ergometer stand framework is attached a standard ergometer 21provided with adjustable strap pedals 20 for operation of the exercisingdevice. The instrumentation shown is a read-out meter system 22connected by means of electrical leads 24 and 25 to the ergometer 21.

While, with other systems the subject 23 (indicated by dashed lines)might also be equipped with a harness device 26, partially shown, suchdevice is not necessary and eliminated by use of the present apparatus,as will be shown.

In operation, the subject being tested sits as shown in the dashed lines23 on seat 5, for example, in FIG. 1, in the upright position. His back,at the point of the shoulders, is substantially over hinge 3 whichpivots plate 2. His hands rest on the handlebars l9 and his feet engagethe pedals 20 of the ergometer 21. The seat 5 acts as a rough index asit projects between the thighs, and the subject's back touches thebackrest firmly enough to make an impression in the resilient padding ofa foam type which would be adapted to contour to the body; and,likewise, the head makes a cradle at the headrest 8. At this point theneck and shoulders make such an angle with the raised headrest thatsubstantial motion along the lengthwise axis of the subject isrestrained. This is also aided by the firm placement of the hands of thesubject on the handlebars 19; which, in turn, together with the seat 5also restrain lateral motion of the body of the subject as exercise isperformed on the ergometer.

, Now, assuming that the subject is in the position shown in FIG. 1, andis using the hand lever 14 to actuate the hydraulic system, he may withone hand on this lever momentarily actuate the lever in one direction tomove the entire apparatus on hinged plate 2 backward through any desiredangle. There is very little body motion, aside from that required topedal the ergometer, exerted in moving the lever 14. The subject mayeither leave his hand on this lever after he has achieved the desiredangle, or may return his hand to the handlebar 19.

In any event, positive stops can be made at any angular position fromthe vertical to the horizontal, at which point the projecting flange onthe hinged plate 2 provides a positive stop in the horizontal positionwith the subject supine. However, it can readily be seen, also, that asthis subject moves through the various angles his body remains indexedin the same relative position with regard to the ergometer. It will benoted that as the subject moves from the vertical to the horizontalposition with the apparatus his body line and legs maintain the samerelative position, indexed on the seat 5; and the legs of the subjectare not placed in a position of further extension, away from the body,as the apparatus tilts backward, nor are they drawn up against his bodyas the subject moves from the horizontal position to the verticalposition, as with other exercise devices heretofore provided.

it is well known that while a subject is exercising in a supine orhorizontal position (either with an ergometer or with any otherbiomedical device), if the trunk of the subject is brought into thevertical position with the attitude of the body so changed that the legsare brought'into a position at right angles, or if the legs are broughtinto position drawn up against the abdomen, the internal organs of thebody are so shifted and strains set up on the arterial and venous systemsuch as to cause drastic changes in the heart rate, circulation rate,and metabolic rate of thetest subject. In summary, changing the attitudeof the body through certain angles during exercise creates certainexternal stresses relative to that created by the exercise alone. Therefore, the test data for a subject under such exaggerated conditions withregard to the position of the body in changing movement would be quitedifferent from the conditions which would be found where the body wasindexed in the same relative position while exercising, with the entirebody attitude being changed through a relative angle of elevation.

It is known that in application to space exploration, an astronaut mightbe indexed into a fixed position on a couch, while performing exercisesas indicated on the apparatus of this invention, with his body attituderelative to the work being done remaining the same, but the overallattitude of his total environment changing relative to the horizontal.it is tests of this nature that are desired to be performed, not onlywith the ergometer, but with other biomedical devices, maintaining thisbody attitude, but free from abnormal stresses which might be broughtabout by drawing the legs up into the trunk and displacing internalorgans.

The present invention offers many advantages. The subject may be fullyinstrumented and tested in any desired position, while producing energyon the ergometer or at rest. This device can be fitted with otherbiomedical instruments, without the ergometer, or the two can be used incombination. If the ergometer is removed, it is desirable to leave theframe if possible so that the seat and handlebars may be used asdescribed or otherwise substitutes may have to be supplied. It will bereadily apparent that with this device no external stresses are put onthe body except those occasioned by the driving motion of the legs inpropelling the ergometer. The back contour remains the same whileexercise can be performed at the various angles. This can be done byoperation of the device through the angles by the subject himself, or itcan be done by remote control or by a programmed cycling device asindicated in the drawings. Many types of instrumentation can be effectedwith this apparatus. A treadmill could be substituted for the ergometerwith angular adjustment of the seat, and an electrocardiogram or ametabolic analyser could be connected into the sytem.

Thus it will be seen that we have provided an apparatus suitably adaptedto meet the objects and features hereinbefore set forth.

From the foregoing it will be seen that the invention is well adapted toattain all of the ends and objects, together with other advantages whichare obvious and which are inherent to the structure.

It will be understood that certain features of any subcombinations ofthe invention are of utility and may be employed without reference toother features and subcombinations. This is contemplated by and iswithin the scope of the claims.

As many possible embodiments of theinvention may be made withoutdeparting from the scope thereof, it is to be understood that allmatters set forth or shown in the drawings is to be interpreted asillustrative and not in a limiting sense.

Having thus described our invention what is claimed l. in a tiltingtable for an ergometer and other biomedical devices, designed to testthe human body in a variety of positions from vertical to supine, of thecharacter described, the combination comprising:

a floor plate providing a base;

a hinged plate pivotally connected to said floor plate and movablethrough a predetermined angle; positive stop means integral with saidhinged plate limiting its angular travel; biomedical testing meansmounted on said hinged plate operable by a test subject; cradling meansfor said test subject mounted on said hinged plate disposed to maintainsubstantially the position of the body of said subject while beingtested, other than the angularity imparted by the test itself, whilesaid subject operates said testing means;

power means tilting said hinged plate through an angular course oftravel such as to move the body attitude of the test subject from thevertical to the supine;

and actuating means for said power means to selectively control thetilting movement of said hinged plate during a test.

2. Apparatus of the character described in claim 1, wherein said hingedplate comprises an elongated stand hinged at one end to said floor plateand movable to describe an arc of relative-to said floor plate.

3. Apparatus of the character described in claim 1, wherein said stopmeans on said hinged plate comprises a vertically disposed flange at thepivotal end of said plate having an occluding edge relative to saidfloor plate restricting angular travel of said hinged plate.

4. Apparatus of the character described in claim 1, wherein saidbiomedical testing means comprises an ergometer with a stand andhandlebars mounted on said hinged plate; pedals on said ergometersupporting the feet of a test subject; a seat connected to said standsupporting said subject with said handlebars while operating saidergometer; and read out instrumentation connected to said subject andergometer.

5. Apparatus of the character described in claim 1, wherein saidcradling means comprises:

a saddle seat projecting between the thighs affixed to said hingedplate;

a bar support for the hands integral therewith;

a frame projecting substantially at right angles from the pivotal end ofsaid hinged plate and rearwardly of said seat;

a padded back rest of resilient material supported by said frame,yieldably contouring itself to the body of said test subject;

a head rest affixed to said back rest in raised contour supporting thehead and nesting the shoulders;

said back and head rest cooperating to index a test subject on said seatsuch as to maintain said body position in substantially the samerelative attitude thereto, through all degrees of angularity imparted tosaid hinged plate, from vertical to supine.

6. Apparatus of the character described in claim 1, wherein said powermeans comprises a hydraulic piston and cylinder system operablyconnected between said floor plate and hinged plate assembly such as topivotally urge said hinged plate in reciprocal movement from flushposition to one at right angles thereto when actuated.

7. Apparatus of the character described in claim 1, wherein saidactuating means comprises a manually operated two-way switch mounted injuxtaposition to said cradling means such as to be operable by one handof said test subject while maintaining the remainder of the body of saidsubject in test mode.

8. Apparatus of the character described in claim 1, wherein saidactuating means comprises a remote control switch for said power meansoperable by one other than said test subject.

9. Apparatus of the character described in claim 1, wherein saidactuating means comprises a remote control automatically programmedswitch for said power means operable to program said tilting mechanismthrough a predetermined cycle of movement.

l l I! t l

1. In a tilting table for an ergometer and other biomedical devices,designed to test the human body in a variety of positions from verticalto supine, of the character described, the combination comprising: afloor plate providing a base; a hinged plate pivotally connected to saidfloor plate and movable through a predetermined angle; positive stopmeans integral with said hinged plate limiting its angular travel;biomedical testing means mounted on said hinged plate operable by a testsubject; cradling means for said test subject mounted on said hingedplate disposed to maintain substantially the position of the body ofsaid subject while being tested, other than the angularity imparted bythe test itself, while said subject operates said testing means; powermeans tilting said hinged plate through an angular course of travel suchas to move the body attitude of the test subject from the vertical tothe supine; and actuating means for said power means to selectivelycontrol the tilting movement of said hinged plate during a test. 2.Apparatus of the character described in claim 1, wherein said hingedplate comprises an elongated stand hinged at one end to said floor plateand movable to describe an arc of 90* relative to said floor plate. 3.Apparatus of the character described in claim 1, wherein said stop meanson said hinged plate comprises a vertically disposed flange at thepivotal end of said plate having an occluding edge relative to saidfloor plate restricting angular travel of said hinged plate. 4.Apparatus of the character described in claim 1, wherein said biomedicaltesting means comprises an ergometer with a stand and handlebars mountedon said hinged plate; pedals on said ergometer supporting the feet of atest subject; a seat connected to said stand supporting said subjectwith said handlebars while operating said ergometer; and read outinstrumentation connected to said subject and ergometer.
 5. Apparatus ofthe character described in claim 1, wherein said cradling meanscomprises: a saddle seat projecting between the thighs affixed to saidhinged plate; a bar support for the hands integral therewith; a frameprojecting substantially at right angles from the pivotal end of saidhinged plate and rearwardly of said seat; a padded back rest ofresilient material supported by said frame, yieldably contouring itselfto the body of said test subject; a head rest affixed to said back restin raised contour supporting the head and nesting the shoulders; saidback and head rest cooperating to index a test subject on said seat suchas to maintain said body position in substantially the same relativeattitude thereto, through all degrees of angularity imparted to saidhinged plate, from vertical to supine.
 6. Apparatus of the characterdescribed in claim 1, wherein said power means comprises a hydraulicpiston and cylinder system operably connected between said floor plateand hinged plate assembly such as to pivotally urge said hinged plate inreciprocal movement from flush position to one at right angles theretowhen actuated.
 7. Apparatus of the character described in claim 1,wherein said actuating means comprises a manually operated two-wayswitch mounted in juxtaposition to said cradling means such as to beoperable by one hand of said test subject while maintaining theremainder of the body of said subject in test mode.
 8. Apparatus of thecharacter described in claim 1, wherein said actuating means comprises aremote control switch for said power means operable by one other thansaid test subject.
 9. Apparatus of the character described in claim 1,wherein said actuating means comprises a remote control automaticallyprogrammed switch for said power means operable to program said tiltingmechanism through a predetermined cycle of movement.